Transcript WWW Tutorial

Microsoft Networking
M. Ghouseuddin
[email protected]
Department of Information & Computer Science
KFUPM, Dhahran, Saudi Arabia
Overview
Some important Network Services of
Windows 2000
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Domain name system (DNS)
Dynamic Host Configuration Protocol (DHCP)
Dynamic DNS (DDNS)
Domain Name System
DNS
DNS- Overview
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Define DNS
DNS Installation
Zone creation
» Forward
» R e v e rs e
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Test DNS
Zone transfer
Installation
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Pre-Requisites for installation
» Assign a static IP address to the machine
» Configure the DNS settings for TCP/IP
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Installation can be done during W2000 setup or after
the setup
Installation (Contd ..)
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Go to Add/Remove Programs in control panel
Click Add/Remove Windows Components
Click Networking Services/Details
Select DNS to install the service
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Configure the DNS through Administrative tools
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Installation (Contd ..)
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Follow these steps to confirm the installation
» Go to Settings/Control Panel/Administrative Tools/Services
» Check the DNS server service
» Go to Systemroot\system32\dns folder
» This folder should contain
– mssc.dns
– cache.dns
– boot
Define Zone
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A zone is a portion of your name resolution DB
Forward lookup zone
» Resolves hostnames to IP addresses
» ccse-funny -> 196.1.66.55 (ping command)
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Reverse lookup zone
» Resolves IP addresses to hostnames
» 196.1.66.55 -> ccse-funny (nbtstat command)
Forward Zone
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Open DNS manager
Configure the server(server = computer name)
Specify the zone type
» Primary
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Specify the zone name
» mssc.kfupm.com
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Specify the zone file name
» mssc.kfupm.com.dns
Reverse Zone
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Open DNS manager
Configure the server(server = computer name)
Specify the zone type
» Primary
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Specify the network id
» 196.1.66
Test DNS
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DNS Console Monitor
» Self test
» Recursive test
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Nslookup
» Nslookup “DNS computer name”
» Specify the ip address or host name to be resolved
Zone transfer
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Master server
» Maintains the complete database
» Updates are done to this zone
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Secondary server
» Receives the database from the master
» Useful in terms of less maintenance
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Types of zone transfer
» Full transfer
» Incremental transfer
Zone transfer
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Transfer properties
» Serial Number
– Tracks update to zone db
» Refresh, Retry, expire intervals
– Update request intervals
Dynamic Host
Configuration Protocol
DHCP
DHCP
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Dynamic host configuration protocol
Used for dynamic configuration of essential network
parameters e.G. TCP/IP parameters
» TCP/IP parameters: IP address, DNS address, WINS
address etc.
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DHCP clients request DHCP servers for network
parameters using DHCP protocol
Why DHCP ?
Large networks constitute of many hosts. Therefore
configuring network parameters on all hosts is a timeconsuming task.
 Network may have a small pool of addresses & lot of
computers. Reuse of IP addresses is possible because
only a few hosts are expected to use their IP address at
a given time.
 Network restructuring may result in change of host
subnets, thereby necessitating change in network
parameters.
 Networks may have mobile computers.
Without DHCP, network parameters would need to be.
Configured manually.
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DHCP Operation
Client.
 Client must be configured to use DHCP.
 Client broadcasts request for network parameters.
 Client gets network parameters from the DHCP server
for specified lease times.
Server.
 Maintains database of network parameters for
different machines or groups of machines (called
scopes).
 Manages lease times for all machines.
DHCP Lease Times
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Lease period
» Amount of time a client can hold network parameters
assigned by the DHCP server
» When this time expires client surrenders its IP address
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Renewal period
» = 0.5 x lease period
» On expiry, host starts trying to renew its lease
IP Address Management
DHCP server uses three methods for IP address:
 Static allocation
» IP address is tied to MAC address of client
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Automatic allocation
» DHCP server assigns an IP address with an infinite lease
period
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Dynamic allocation
» IP address assigned on a temporary basis (for lease period)
» Revokes the client on expiry of the lease
» Client can request for renewal or another IP address at end
of lease period
Useful in an environments where temporary connections are
Required or when IP addresses are scarce
Configuring DHCP Scopes
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Each subnet may be configured as a scope.
» A scope is a grouping of DHCP clients.
» All network parameters for computers of a given scope are
the same.
» A scope may be assigned a pool of IP addresses.
» Scopes allow exclusion ranges within the scope.
DHCP Installation
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Control Panel
Add/Remove Programs
Add/Remove Windows components
Networking Services/Details
Select DHCP
Click on OK. This will complete the installation
Configure a Scope
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Requirements
»
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Scope Name (66 Network Segment)
IP Address Range (196.1.66.0 to 196.1.66.254)
Unique subnet mask (255.255.255.0)
IP Addresses exclusion list
Lease duration (4 Hours)
DHCP options
– DNS servers
– WINS servers
– Gateway address
Configure Scope
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Open DHCP console
Right click on server & select New scope
Specify all the previously mentioned options
Activate the scope
Dynamic DNS
DDNS
Dynamic DNS
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Why Dynamic DNS
Dynamic DNS
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Need for DDNS
Update Protocol
Definitions
DDNS operation
DDNS Advantages
Why Dynamic DNS
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Designed to overcome weakness of Conventional
DNS (C-DNS).
C-DNS needs manual update of host information.
Manual update takes lot of time even in small
networks.
C-DNS does not integrate with DHCP.
C-DNS stores stale records.
Dynamic Update Protocol
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DNS client locates the server for information update
Sends a message to register with DNS
If registration exists re-register
DDNS Operation
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DNS dynamic updates are generated by the DHCP
service at the client machine
Functionality at both the client side & the DHCP
server
DDNS Operation (Contd.)
DHCP client – At bootup
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Client proposes to update the A resource record
DHCP Server updates the A & PTR record
DHCP client – At shutdown or IP release
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DHCP server removes PTR R
Removes A Record if configured for that
DDNS Advantages
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Helps in automation of DNS updates for new hosts
Obsolete information is not entertained
Allows frequent changes in IP addresses
Dynamic DNS
Demo